Crease-proofing cellulosic fabrics, the fabrics obtained and methods of making them



2,940,817 Patented June 14, 1960 (TREASE-PROOFING CELLULOSIC FABRICS,

FABRICS OBTAINED ING THEM 19 Claims. (Cl. 8-1163) THE AND METHODS OF MAK- The present invention relates to an improved process for the treatment of cellulosic fabrics, especially cotton and rayon, for the purpose of increasing resistance to creasing, to crushing, wrinkling, and of reducing the tendency to shrinkage on laundering. The invention is particularly concerned with the process of crease-proofing cellulosic fabrics or other textile materials of cellulosic type and to the improved products obtained.

It is an object of the present invention to provide a process for increasing the resistance of cellulosic fabrics to creasing, crushing, and wrinkling by means of a cross-linking agent, which, in reacting with the cellulosic materials, does not form a resin on the textile materials so that it efifects the crease-proofing and so on without essentially modifying the hand or optical characteristics of the textile material. Another object of the present invention is to provide a process for increasing the resistance to creasing and the like of cellulosic textiles by means of cross-linking agents which enhance the receptivity of the textile materials to dyeing. While such an improvement in receptivity to acid dyes might be expected because of the basic nature of the cross-linking agent, the surprising discovery has been made that the cross-linked products of the present invention also have markedly improved receptivity to other conventionally used classes of dyestuffs, such as direct dyes and especially to acid dyes. Another object of the invention is to provide improved modified cellulosic textiles. Other objects and advantages of the invention will be apparent from the description thereof hereinafter.

The use of thermosetting resin-forming condensates, such as those of formaldehyde with urea, melamine or other nitrogen-containing compounds, for the purpose of increasing the resistance of cellulosic fabrics to creasing and the like is known. These resin-forming materials, however, are generally characterized by the deposition of a substantial amount of resin on the surface of the fibers of the textile material which modifies the hand, frequently in a disadvantageous manner, as by harshening the hand or feel of the textile material.

In accordance with the present invention, cellulosic fabrics are improved in their resistance to creasing, crushing, wrinkling, and tendency to shrink on washing by reaction with the salt of a poly(vinyloxyalkyl) amine which, under the conditions of reaction, reacts exclusively with the hydroxyl groups of the cellulosic molecules in the textile material and does not form a resin deposit on the surface of such fibers or in or on the textile fabric. The poly(vinyloxyalkyl) amine, the salt of which is used for effecting the reaction of the present invention may be any of those having the general Formula I:

n is an integer having a value of 2 to 3, R is selected from the group consisting of cyclohexyl, benzyl, and alkyl groups having 1 to 8 carbon atoms,

A is an alkylene group having 2 to 4 carbon atoms,

and X is selected from the group consisting of Oand S.

In the formula, at least two carbon atoms of the alkylene group extend in a chain between the X atom and the nitrogen atom. Examples of alkylene groups that may be employed include ethylene, trimethylene, propylene, in which one of the carbon atoms of the ethylene group extending between the X and N atoms is substituted by a methyl group, and isobutylene, where one of the carbon atoms of the ethylene group extending between the nitrogen and X atoms is substituted by two methyl groups. The alkyl groups which may represent R include methyl, ethyl, n propyl, isopropyl, n-butyl, isobutyl, secbutyl, t-butyl, hexyl, n-octyl, and t-octyl.

The salts of the amine may be formed from any suit able acid such as inorganic or mineral acids, of which hydrochloric acid, phosphoric acid, nitric acid, sulfuric acid, and perchloric acid are representative, or it may be any organic acid, such as a monobasic acid of the aliphatic series, including formic acid, acetic acid, propionic acid, and so on, or it may be a polycarboxylic acid, such as maleic acid, fumaric acid, succinic acid, citric acid, adipic acid, sebacic acid, oxalic acid, phthalic acid, or tartaric acid. If desired, the salt may be formed by the use of a mixture of two or more different acids, such as a mixture of an organic acid with a mixture of an inorganic or mineral acid in any desired proportions. The amines of Formula I are generally insoluble in water but the salts conveniently are quite water-soluble. The salts may be prepared by simply dispersing the amine in water with agitation and adding acid during the agitation until the amine is completely dissolved. Of the various acids mentioned hereinabove, the preferred salts are obtained by the use of formic acid, acetic acid, maleic acid, nitric acid, fluoboric acid, or perchloric acid as the treated fabrics obtained using the amine salts ofthese acids exhibit negligible or a complete absence of discoloration as a result of the treatment. The amine salts of the other acids are useful, however, when dyed or otherwise colored textile materials are treated where the discoloration is not noticeable.

The amine salt may be applied to the textile material in any suitable way. Thus, an aqueous solution thereof having any desired concentration may be prepared and the textile material may be treated with such solution by dipping, spraying, brushing, by transfer rollers, by the use of a textile pad or any other suitable and conventional equipment or system. Generally, after the solution is applied, excess may be removed as by squeezing or squeegeeing. When application is by a procedure where approximately wet pick-up occurs, the concentration of the salt may be from 5 to 20% for most purposes. Optimum results are generally obtained when 8 to 12% concentration of the salt in the aqueous system is applied at about 100% wet pick up. After application and any desired removal of excess, the textile material is dried. This may be eifected simply by drying in ambient air or by the application of heated air, by infrared heat, or by high frequency electric induction procedures. The particular equipment employed may be selected depending upon the particular type of textile material treated.

The treatment of the present invention may be applied to any textile material containing cellulosic fibers .or yarns and the textile material may be in the form of woven or knitted fabrics, non-woven fabrics derived from carded webs or from fibrous or filamentous webs obtained in any suitable fashion, such as air-deposition, wherein the fibers or filaments are distributed in a haphazard array. The treatment may also be applied to a V V 2,94o,s17

a a V, 7 V g} yarns, threads or other plied structures, or it may be bing, matting, or batting. In all fibrous structures having the fibers inhetefogeneoiis array, theftre'a'tment "renders the textile more resilient. V

'The fabrics or fibrous n:1r.1ss'es that maybe treated are applied to fibers or filaments in the form of loose or bulk masses or in the form of more or less compacted web-' those which contain a predominantproportion of cellulosic fib'e'rs and/or filaments, by whichis meant that the ,cellulosicfibers constitute more than 50% ,of the total :fib'ers weight. It is particularly useful with textile materials of cotton, viscose rayon, cuprammonium cellulose rayon, linen, ramie, as well as textile materials cornin which thej'amine reacts with the cellulose by addition of the unsaturated group to the hydroxyl group of the cellulose to form an acetal linkage between the crosslinl ringbridge and the cellulosis molecules. The heating shouldbe in'a range of temperature from about 250 tojlOO" F.- for a period of about one-half minute to an hour, the shorter time being usedwith the higher temperaturcandvi'ce versa. In any case, the upper limit of temperature should'not be so high as'to damage the fibers in the fabric by thermal decomposition. Preferably, a temperature bfBOO to 350? F. is employed. At'a temperature of 325 F,,-a short period of about 2 /2 to 3 niinute s'is entirely adequate, whereas at 300 F. the time generally-needed is about 15 minutes; The amine salt is'self-catalytic-in that no other material is. needed to effect the reaction between the cellulose and the crosslinking agent at the elevated temperature specified.

' 'As' 'rn'entioned hereinbefore, the cross-linking agents of'the present invention do not appreciably modify the hand ot-feel of the textile material. They also improve receptivity to acid dyes. The cross-linked textiles are quite resistant to alkaline materials and, on being subjected to heat, they undergo substantially no loss in strength even 'w hen-such heat'is elevated to a scorch' i'n'g temperature where discoloration is effected.

. If desired, the treatment with the amine salt may be supplemented-by a treatment with a hand modifier or builder, softened, Water-repellent agents, or 1 materials which enhance the crease-resistance that can be obtained by means a of the cross-linking agent. Such modifying agents may be applied simultaneously byway of the same aqueous solution of the salt or they may be applied to the fabric before or after the application of the amine salt by means of a separate operation. Such additional modifying agents may be applied advantageously by a separate operation after the completion of the cross-linking by means of the amine of the present invention. e

r As water-repellent materials which also serve to soften resistance which can be applied in aqueous media include aqueous dispersions of water-insoluble linear addition polymers of one or more monoethylcnically unsaturated monomeric compounds. Eiramples include water-insoluble copolymers of 0.5to 8% by weight of acrylic acid, methacrylic acid, and itaconic "acid; Any one or more of these monoethylenically unsaturated. acids may be copolymerized with-Queer more other copolymerizable compounds containing a 'single' vinylidene group, such as esters of acrylic acid or methacrylic acidand monohydric alcohols such as methyl, ethyl, butyl, octyl, 'dodecyl, cyclohcxyl, cyanoethyl, aminoethyl, and the flike;

esters of itacom'c acid and the above alcohols; esters from maleic, fumaric or citraconic acids,-and the above'alcohols; vinyl esters of carb'oiylic acids such as acetic, propionic, butyric, and th'e'like; vinyloxyalkyl esters such a as vinyloxyethyl acetate, etc.; vinyl ethers such as ethyl vinyl ether, butyl vinyl ether, octylvinyl ether, hydroxyethyl vinyl-ether, aminoethyl-vinylether, aminopropyl vinyl ether, dirne'thylaminoethyl' vinyl ether, vinylo'Xy', 'ethoxyethan'ol, vinyloXypropoXyethanol; methacrylonitrile or 'acrylonitrile, acrylamide, or methacrylamide, and N-substituted amides of these types; vinyl chloride, vinyl bromide, vinylidene' chloride, vinylidene fluoride, vinylidenscyanide, 'l chloro-1-fluoroethylene, ethylene, styrene, 2vinylpyridine, 4-vinylpyridine, '2-methyl-5-vinyl pyridine. These water-insoluble copolymers may be dispersed by means of non-ionic dispersing agents, such as alkylphenoxypolyethoxyethanols having alkyl groups of about seven to eighteen carbon atoms and six to sixty or 'more oiryethylene units, such as heptylphenoxypoly ethoxyethanols, octylphenoxypolyethoxycthanols, methyloctylphcnoxypolyethoxyethanols, V nonylphcnoxypolyeth- .oxyethanols, dodecylphenoxypolyethoxyethanols, and the like; polyethoxyethanol derivatives of methylene linked alkyl 'phenols;' sulfur-containing agents such as those vention may be a dyed fabric but, ifnot, the pigments and/ or dyes may be included in the aqueous solution used 7 These quaternary ammonium salts, are water-soluble in Y the salt form and they can, therefore, readily be included within the aqueous solution of the amine salt; The amount of water-repellent or softener -may be as much Examples ofauxiliary agents for-enhancing the creasein the examples are performed on the treated fabric after made by condensing six to sixty or more moles of ethylene oxide with'nonyl, dodecyl, tetradecyl, t-dodecyl, I

and the like mercaptans or with alkylthiophenols having alkyl groups of six'to fifteen carbon atoms; ethylene oxide derivatives of long-chained carboxylic acids, suchas lauric,;-myristic, palmitic, oleic,'an'd the like or rnixtures of acids such as found in 'tall oil containing sixto sixty oxyethylene units per molecule; analogous ethylene oxide condensates of long-chained alcohols, such as ocryl,

decyl, lauryl, or-cetyl alcohols,fethylene oxide derivatives of etherified or esterified polyhydroxy compounds having a hydrophobichydrocarbon -Ch1l11,"SllCi1 as. sorbitan monostearate containing-six to sixty oiiyethyleneunits, etc.; block copolymers of ethylene oxide and propylene oxide comprising a hydrophobic propylene oxide section' combined with one or more hydrophilic ethylene oxide sections. The concentration *of the water-insolublepolysalt or before or after the application'of the amine salt. These auxiliary crease-proofing agents maybe 'usedin amounts which serve to modify the hand from a soft-to a firm or stiff hand depending upon what is desired and depending upon theselection ofcomonomers used in any copolymer thus applied. y

The fabric treated in accordance with the present in-- en ma em -l agent or n other auxili y treating agent. A dye 0r,,pigment.; appliedgby,

printing orayeing the fabric after'the completion'of the orease-Tproofingtreatment of the present-invention.

lnthe folldvyingfexamples, which are illustrative of the present invention, the parts and percentages are by weight.

unless other indicated; The tcsts"whose results are given being conditioned at 70? .F. and 65% relativehumidity,

The crease-recovery ang'le'is'the anglebbtained by'thestandard methodpftesting therefor. The tensile'sti'en'gth' in wins. and...

1 l i l l EXAMPLE 1 (a) 1.5 In. of methyl(di-(2-vinyloxyethyl))amine are suspended with stirring in 50 ml. of water yielding a pH of about 10 to 11. Then a solution in water of formic acid having a concentration of 50% is added until the amine dissolves (about 5 to 6 ml. being required), yield-' ing a pH of 5 to 6. The solution is then diluted to'l00 ml. and at this concentration is applied at 100%. wet pick-up to an 80 by 80 cotton fabric. The treated fabric after removal of excess solution is dried by heating for five minutes at 240 F. and is cured for five minutes at 325 F. It is then washed with an alkaline detergent, dried, conditioned, and tested. Table A compares the properties tested of treated and untreated fabrics.

The treated fabric is dyed with Orange II (Color Index No. 151) and takes on a deep orange color much deeper than the untreated fabric dyed under the same conditions with the same dye.

(b) In the same way, a fabric having a similarly improved crease-recovery angle is obtained by the procedure of part (a) substituting 7.5 ml. of methyl(di-(2-vinylthioethyl) )amine.

(c) The procedure of part (a) is repeated substituting 7.5 ml. of n-butyl(di-(Z-vinyloxyethyl))amine for the amine used in part (a). Results: Crease-recovery angle 110, tensile strength 26.5, and Elrnendorf tear strength 2. The treated fabric is dyed with Direct Brilliant Blue SBC (Color Index No. 466). A deep blue shade is obtained whereas the untreated fabric is tinted only to a very light blue shade.

(a) The procedure of part (a) is repeated with similar results substituting 7.5 ml. of cyclohexyl(di-(2-vinyloxyethyl) )amine for the amine of part (a).

(e) In the same way, a fabric having a similarly improved crease-recovery angle is obtained by the procedure of part (a) substituting 7.5 ml. of benzyl(di-(2-vinylthioethyl) )amine.

(f) In the same way, a fabric having a similarly improved crease-recovery angle is obtained by the procedure of part (a) substituting 7.5 ml. of n-octyl(di-(2-vinylthioethyl) )amine.

EXAMPLE 2 The procedure of Example 1 is repeated except that the amine is replaced with 10 ml. of tri(2-vinyloxyethyl) Y EXAMPLE 3 (a) ml. of methyl(di-(2-vinyloxyethyl))amine are suspended in 50 ml. of water and neutralized with 25% g aqueous formic acid yielding a pH of 5.5 to 6. After dilution to 100 ml., an 80 by 80 cotton fabric is treated with the solution as in Example 1, excaptthe drying is effected in air instead of at 240 F. The results of the tests are as follows:

Table C Untreated Treated Fabric Fabric Crease-Recovery Angle. degrees 69 116 Tensile Str 39. 7 26. 5 Elmendort Tear Strength 43 19 (b) The procedure of part (a) hereof is repeated except that three ml. of an aqueous dispersion of poly(butyl acrylate) (35% solids) is added to the neutralized solution before dilution to 100 ml. The treated fabric has a crease-recovery angle of 130, a tensile strength of 21.3 lbs/inch and a tear strength of 27. v

(c) The procedure of part (a) hereof is repeated except that before conditioning the treated fabric for testing it is padded through an aqueous dispersion containing 1% of poly(buty1 acrylate) obtained by dilution of an emulsion polymer thereof. The application of this dispersion is effected at 100% wet pick-up, the fabric is dried five minutes at 240 F., cooled and then conditioned. It has a crease-recovery angle of 131", a tensile strength of 21.3 V

lbs./inch and a tear strength of 27.

EXAMPLE 4 5 ml. of methyl(di-(2-vinyloxyethyl))amine are suspended in 50 ml. of water and neutralized with 30% aqueous acetic acid to a pH of about 6 and diluted to about 100 ml. The resulting solution is applied to an by 80 cotton fabric at wet pick up, and after treatment was brought to 325 F. for ten minutes .to.

effect drying and cross-linking. After washing, drying and conditioning, the results are tabulated:

ml. of methyl(di-(2-vinyloxyethyl) )amine are used instead of 5 ml. The treated fabric obtained has a creaserecovery angle of 99, a tensile strength of 30.6 lbs./ inch and a tear strength of 26.

EXAMPLE 6 10 ml. of methyl(di-(2-vinyloxyethyl) )amine are suspended with stirring in 40 ml. of water. Several solutions are made in this way and then neutralized to a pH of 6 with a 5 N solution of each of the following acids. After dilution to 100 ml., a separate 80 by 80 cotton fabric is treated in each of the solutions and the procedure of Example 4 is followed. In the following table, the results of testing the conditioned fabric are presented alongside the respective acid used and the treatment.

Table E Crease- Tensile Elmendort Acid Recovery, Strength Tear degrees Strength where if with an aqueous acidic solution of a" water-soluble salt of an acid with an amine of theformul'a 1 n is an integer-having a 'value of 2 to 3,

V R is a member selected from the group consisting of TableF Crease- Tensile Elmendorf Acid Recovery, Strength Tear degrees e oxalic; 119'? fine-9a 3'22 Phthalic 103' 3021' 25 Succin1e.- 108 1.9 -23 EXAMPLE 8 .10 of methyl(di-(2rvinyloxyethyl))amine-are sus-- pended in 40 ml. of water and neutralized to a'pH' of :6 with 5N solutions of the following inorganic acids. After dilution to 100 m1. and application at. 100% wet pick-up to an -80 by '80 cotton fabric. each fabric thus treated isheated. at 325 F. for 10 minutes to effect drying and cross-linking. After washing, drying and conditioning, the'results obtained are as indicated in the following table:

Table 6' Crease- Tensile Elmendorf Acid Recovery, Strength Tear degrees Strength suuanc-- 127 25.7 19 Hydrochloric- 119 22. 3 18 Phosphoric- 120 25. 5 Nitric- 98 24. 0 20 Fluoborlc. 98 28. 7 23 Perchloric 108 25. 0 21 EXAMPLE 9 Sixty parts of a solution of formic acid in water 1 is mixed with 40 parts at a, 25% solution of sulfuric acid in water and used to neutralize a suspension of 10 ml. of methyl(di-(2-vinyloxyethyl) )amine in 50 ml. of water to--a pH-of 6. After dilution to 100ml; an '80 by 80 cotton fabric is treated with the solution at 100% wet pick-up, air-dried, and then 'heateddive minutes at 325 F. It is washed, dried: conditioned. "ihe creaserecove angle of the warp is 126 the tensile strength of the warp is 29.2 IbSL/inch'and'the 'Ehnendorf tear strength across thewarp is 30. 7

' EXAMPLE 10' V 2f) ml. "of methyl ('di-(2-vinyloxyethyl) )amine are suspended in 40 ml. of water and neutralized to a' pH of 5.5 using 25% aqueous formic acid. The solution is diluted to 100 ml. and a rayon fabric is treated at 100% wet pick-up with the solution, air-dried, heated five minutes at presented the following table. Reference to tests on the warponly; V I i I It 'isjtobe understood that changes and variations may be. made without departing from the spirit and scopeof the invention as defined in the appended brains; 7 V

1 daimi Q1711". :QQQII'ILTI 1. As an article 'of manufacturq-a-textile: material comprising cellulose fibeisi cross-linked impregnation 325 F.; washed, dried and conditioned. Theresuits are t V TabIeH Untreated Treated Fabric Fabric Crease-Recovery Angle... ".degtees- 93 V 110 Tensile Strength 63.8 65.0 Elmenduri Tear Strength .Q V 127 f cyclohexyl, benzyl, and, alkyl groups. having =1 to 8 Ycarbon atoms, 7 v Q 7 a V A is' an alkylene group'having 2 to 4 carbon atoms,

and-. j X-is. a me'mberselectedfrom the group consisting of O .and S, v and subsequent heating of the impregnated materialat a temperature of about 250 to 400 'F. until cross-linking of the cellulose is obtained. 7 o V e 2. An article'of manufacture as' defined in claim ,1 in which. the textile material comprises cotton fibers crosslinked as defined in claim 1.

3. An article of manufacture as defined in claim 1 in which the textile material comprises regenerated cellulose fibers cross-linked as defined in claim 1.

4. As an article of manufacture, a textile material" comprising cellulose fibers cross-linked by impregnation with an aqueous acidic solution of a water-soluble saltof an acid with methyl(di-(2'vinyloxyethyl))amine and subsequent heating of the impregnated .rnaterial at a temperature of about' 250 to 400 'F. until cross-linking of the cellulose isobtained.

5. As an article of manufacture, a textile material comprising cotton fibers cross=linked by impregnation with an aqueous acidic solution of a water-soluble salt of an acid with methyl(di-(Z-vinyloxyethyl))amine and subsequent heating of the impregnated material at a temperature of about 250 to 400 F. until cross-linking of the cellulose is obtained. 7

6. As an article of manufacture, a textile material comprising regenerated cellulose fibers cross-linked by impregnation with an aqueous acidic solution of a watersoluble salt of an acid with methyl(di-'(2-vinyloxyethyll) amine and subsequent heating of the impregnated material at a temperature 2 of about 250 to 400 until cross-linking ,of the cellulose isobtained.

7. As an article of manufacture, a textile material cross-linked by impregnation comprising cellulose fibers with an aqueous acidic solution of a Water-soluble salt ofr an acid with tri(2-vinyloxyethyl)'amine and subsequent heating of the'impregnated material at a temperature of about 250 to 400 F. until cross-linking of the cellulose isobtained.

8. A process of treating a fabric of cellulose. fibers I which comprises impregnating the fabric with an aqueous acidic solution of a water-soluble salt of an acid with an amine of Formula I and subsequently heating. the impregnated fabric at a temperature of'about 250 to 400 F. until cross-linking of the cellulose isobtained, Formula I being where n is an integer having a value of 2 to 3, R is a member selectedfrom the group consisting of cyclohexyl, benzyl, and alkylgroups having 1 to 8 carbon atoms, A is an alkylene group having 2 to 4 carbon atoms, and

X is a member selected from the group consisting of O andS.

9. A process as defined in claim 8"in which the salt 12. A process as defined in claim 8 in which the salt is that of perchloric acid.

13. A process as defined in claim 8 in which the salt is that of acetic acid.

14. A process as defined in claim 8 in which the salt is that of a mixture of formic and sulfuric acids.

15. A process of treating a fabric of cellulose fibers which comprises impregnating a fabric of cellulose fibers with an aqueous acidic solution containing about 5 to 20% of a Water-soluble salt of an acid with an amine of Formula I and subsequently heating the fabric at a temperature of about 250 to 400 F. until cross-linking of the cellulose is obtained, Formula I being where 16. A process as defined in claim 15 in which the fabric is a cotton fabric.

17. A process as defined in claim 15 in which the fabric is a regenerated cellulose fabric.

18. A process of treating a fabric of cellulose fibers which comprises treating a fabric of cellulose fibers with an aqueous acidic solution containing about 5 to 20% of a water-soluble salt of an acid with methyl(di-(2- vinyloxyethyl))amine and subsequently heating the fabric at a temperature of about 250 to 400 F. until cross-linking of the cellulose is obtained.

19. A process of treating a fabric of cellulose fibers which comprises treating a fabric of cellulose fibers with an aqueous acidic solution containing about 5 to 20% of a water-soluble salt of an acid with tri(2-vinyloxy ethyl)amine and subsequently heating the fabric at a temperature of about 250 to 400 F. until cross-linking of the cellulose is obtained.

References Cited in the file of this patent UNITED STATES PATENTS 

1. AS AN ARTICLE OF MANUFACTURE, A TEXTILE MATERIAL COMPRISING CELLULOSE FIBERS CROSS-LINKED BY IMPREGNATION WITH AN AQUEOUS ACID SOLUTION OF A WATER-SOLUBLE SALT OF AN ACID WITH AN AMINE OF THE FORMULA 